This problem has been faced by a one of our reader who just upgraded to Windows 7 from Windows Vista, and from day one he started noticing a program called WinSAT.exe which keeps running in the background from time to time automatically. There is no easy way to disable this Experience/Assessment Index Tool in windows 7 as it is not associated with any service, rather it is integrated as scheduled task which runs automatically from task scheduler.
What is WinSAT.exe ?
WinSAT.exe (System Assessment Tool) integrated in windows runs a series of tests and then rates your computer on a scale ranging from 1 through 5. WinSAT.exe actually rates several subsets of your computer system, including processor, memory, primary hard disk, graphics, and gaming graphics.
Lets find out how to stop WinSAT.exe and prevent it from running automatically in future.
Follow the procedure below to disable this process from running.
1. Open Control Panel >> Administrative Tools
2. Double click Task Scheduler
3. Browse to Microsoft\Windows\Maintenance, and Disable the task named "WinSAT"
[ as shown in the image below ]
4. Right click and select disable for WinSAT task in task scheduler.
If the above procedure does not solve the purpose, let us know through comments.